We have examined 129 patients with acute pancreatitis. Intensity of free radical oxidation, lipid peroxidation, antioxidant activity of the blood plasma, severity of systemic inflammatory response syndrome and organ dysfunction/failure were studied depending on the presence of drugs with antioxidant antihypoxant activity in intensive therapy. It was found that an increase in the severity of systemic inflammatory response syndrome is associated with increased content of oxidative stress markers in the blood serum. The inclusion of antioxidants (mexidol, ascorbic acid) in the intensive care of patients with acute pancreatitis can decrease the degree of oxidative stress manifestation, reduces the manifestations of systemic inflammatory response syndrome and incidence of organ dysfunctions.

Acute pancreatitis can quickly progress from mild to severe form due to the formation of proinflammatory mediators and the development of systemic inflammatory response syndrome, activation of reactive oxygen species and lipid peroxidation, disorder of microcirculation. One of the difficult and unresolved tasks ultimately remains possible correction of oxidative stress, defining the role and place of antioxidant therapy in the treatment of acute pancreatitis.

At the initial stage of acute pancreatitis oxidative imbalance develops in the blood due to the intensification of the reactive oxygen species, lipid peroxidation and the formation of reactive oxygen species, which accompanied by compensatory activation of peroxidation protection enzymes in the blood (increased activity of SOD) and depletion of glutation-depending enzymes activity of the blood. Increasing severity of systemic inflammatory response syndrome is associated with high content of markers of oxidative stress in blood.

On the third and seventh day of treatment in patients who received mexidol the severity of systemic inflammatory response syndrome was 23.3% and 23.5% lower than in the comparison group (p <0.05). Reducing of systemic inflammatory response syndrome was also in group with ascorbic acid at the 7th day, and it was significantly lower by 17.6% than in the comparison group (p <0.05).

The degree of oxidative stress was significantly higher in the comparison group, while under treating by antioxidants (mexidol and ascorbic acid) reducing of oxidative stress observed more clearly and quickly.

The duration of treatment, the incidence of infectious complications and mortality were different, but were not credible, while difference in the frequency of organ disorders to the seventh day of treatment were detected (21.9% mexidol group, 22.5% in the group of ascorbic acid against 41.3 % in the comparison group, p = 0.037 and p = 0.044 respectively).